Cable-stayed bridge pylon mortise and tenon type steel-concrete transition segment and manufacturing method and installation method thereof

Abstract

The application discloses a cable-stayed bridge cable tower mortise and tenon type steel-concrete transition segment and a manufacturing method and an installation method thereof, and relates to the technical field of bridge construction. The specific structure comprises the following: an outer wall plate unit; a plurality of skirt wall plate units which are installed at the bottom side of the outer wall plate unit at intervals; a stable support system which is installed inside the outer wall plate unit; a bearing plate block which is installed inside the outer wall plate unit and is located above the stable support system; the bearing plate block comprises the following: a hollow bearing plate which is installed inside the outer wall plate unit; an anchor web plate which is installed at the top of the hollow bearing plate; and a plurality of bearing plate stiffening ribs which are installed on the hollow bearing plate at intervals. The application further discloses a manufacturing method and an installation method of the mortise and tenon type steel-concrete transition segment. The application solves the technical problems of frequent bridge diseases, large cable tower design height and complex structure type caused by the existing steel-concrete transition structure.

Description

Technical Field

[0001] This invention relates to the field of bridge construction technology, and in particular to the mortise and tenon type steel-concrete transition segment of cable-stayed bridge towers and its manufacturing and installation methods. Background Technology

[0002] Steel bridge towers are increasingly widely used in bridge projects spanning major rivers, bays, and other waterways due to their excellent load-bearing capacity, lightweight design, and aesthetic appeal. In cable-stayed bridges, the "steel-concrete" hybrid tower, consisting of a concrete lower tower and a steel upper tower, has gradually become the mainstream. In this type of cable-stayed bridge tower, the steel-concrete transition segment needs to accommodate the changes in shape and cross-sectional shape between the concrete lower tower and the steel upper tower, achieving a smooth transition, while also meeting the functional requirements of transferring the load from the upper tower's cable-stayed area to the concrete lower tower. This often results in a complex structure, which has become a key focus and challenge in the design process of this type of cable-stayed bridge tower.

[0003] Based on different force transmission mechanisms, conventional steel-concrete transition segment connections in steel bridge towers can be classified into three types: fully bearing, shear-transfer, and bearing-shear-transfer. Fully bearing steel-concrete transition segments are typically located at the tower base. Due to the thickness of the bearing plate, the concrete in direct contact with the bearing plate may be crushed. Shear-transfer steel-concrete transition segments embed a portion of the steel tower column's base into the concrete tower column, tower base, or foundation. Because the force transmission mechanism is singular, transferring internal forces to the concrete structure solely through shear force, a relatively long force transmission length is required. Traditional bearing-shear-transfer steel-concrete transition segments have a more complex structure, demanding higher construction techniques and presenting significant manufacturing difficulties. Summary of the Invention

[0004] The purpose of this invention is to provide a mortise and tenon type steel-concrete transition segment for cable-stayed bridge towers, as well as its manufacturing and installation methods, which solves the technical problems of frequent bridge defects, large tower design height, and overly complex structural forms caused by existing steel-concrete transition structures.

[0005] This application discloses a tenon-and-mortise type steel-concrete transition segment for cable-stayed bridge towers, including: External wall panel unit; Multiple skirt panel units are installed at intervals on the bottom side of the outer wall panel unit; A robust support system is installed inside the outer wall panel unit; The pressure-bearing plate is installed inside the outer wall panel unit, and the pressure-bearing plate is located above the stable support system; The pressure-bearing plate body includes: A perforated pressure-bearing plate is installed inside the outer wall panel unit; An anchor web plate is installed on top of the perforated bearing plate; Multiple pressure-bearing plate stiffening ribs are installed at intervals on the hollow pressure-bearing plate.

[0006] This application, by setting up corresponding skirt wall panel units, cooperates with other components to form a mortise and tenon steel-concrete transition force transmission structure, which greatly enhances the connection performance between the steel structure part and the concrete structure part of the pylon and improves the safe service durability of the steel bridge.

[0007] Based on the above technical solution, the embodiments of this application can be further improved as follows: Furthermore, the skirt panel unit includes: Skirt panel; Vertical stiffening ribs are installed on the back of the skirt panel; A transverse stiffening rib is installed on the back of the skirt panel, and the transverse stiffening rib is perpendicular to the vertical stiffening rib; Multiple skirt welding studs are installed on the back of the skirt panel. The beneficial effect of this step is to improve the strength of the skirt panel unit by having multiple components work together.

[0008] Furthermore, the included angle between the skirt panel and the outer wall panel unit is α, where α = 175 ± 3°; Both the outer wall panel unit and the skirt wall panel unit are provided with cable guide anchor holes. The beneficial effect of this step is that the angle design can ensure that the entire structure has better mechanical properties.

[0009] Furthermore, the outer wall panel unit includes: Multiple upper wall panels are spaced apart around the perforated pressure plate; Multiple upper corner plates, each of the upper corner plates being disposed between any two adjacent upper wall plates; Multiple lower wall panels are spaced apart around the stable support system; Multiple lower corner plates, each of the lower corner plates being disposed between any two adjacent lower wall plates; Multiple wall panel welding studs are respectively installed on the back of the upper wall panel, lower wall panel, upper corner panel and lower corner panel; The stable support system is composed of multiple horizontal, vertical, and diagonal braces connected in an interlaced manner.

[0010] This application also discloses a method for manufacturing a tenon-and-mortise type steel-concrete transition segment for a cable-stayed bridge tower, including the following steps: S1: Fabrication of upper wall panel, lower wall panel, upper corner panel, lower corner panel, anchor web, bearing plate, skirt panel and stabilizing support system; S2: Place multiple pressure plates on the assembly jig and assemble them. After assembly, a hollow pressure plate is formed. Then, the flatness is checked and adjusted to ensure the flatness of the hollow pressure plate. S3: Assemble the upper wall panel and upper corner panel symmetrically around the hollowed-out pressure plate. After assembly, perform angle detection and adjustment. After precise adjustment, secure the plate and use channel steel for support and protection. First, symmetrically weld the vertical penetration fillet weld between the upper wall plate and the upper corner plate. When welding the vertical penetration fillet weld, use single-sided welding with double-sided forming CO2 gas shielded welding, with the bevel facing outward. The gas shielded welding material is flux-cored wire T554T1-1C1A-N3UH5. Finally, symmetrically weld the circumferential bevel fillet weld between the hollow bearing plate and the upper wall plate and the upper corner plate. S4: Install the anchor web plate onto the hollow bearing plate, while ensuring the verticality of the anchor web plate. After adjusting it into place, secure it and use channel steel for support and protection. First, complete the vertical full-penetration fillet weld between the anchor web and the upper wall plate. Then, symmetrically weld the horizontal full-penetration fillet weld between the anchor web and the hollow bearing plate. Finally, symmetrically weld the full-penetration fillet weld between the bearing plate stiffening rib and the bearing plate to form the bearing plate body. In addition, weld the wall plate studs on the inner walls of the upper wall plate and the upper corner plate using the electric arc stud welding method. S5: The top edge of the pressure plate is machined and milled to ensure the flatness of the top edge; S6: Install the lower wall panel onto the assembly jig, then assemble the skirt panel along the longitudinal direction of the lower wall panel, and weld the butt weld. After the butt weld is completed, turn the lower wall panel over so that the inner side faces upward, and use the arc stud welding method to weld the wall panel welding studs to the lower wall panel. At the same time, use the arc stud welding method to weld the skirt panel welding studs to form two units. Use the arc stud welding method to weld the wall panel welding studs to the lower corner plate. S7: Turn the pressure-bearing plate over 180° and place it upside down on the jig; First, the stable support system is set on the jig, and the two-piece unit is assembled to the upper wall of the pressure-bearing plate. After completion, the two-piece unit is constrained to the steel support frame of the stable support system to prevent the plate unit from overturning. Then, the lower corner plate is assembled between the two adjacent units; the vertical penetration fillet welds between the lower wall plates and the lower corner plates of the two units are symmetrically welded, and the circumferential butt welds between the lower wall plates and lower corner plates of the two units and the upper wall plates and upper corner plates are symmetrically welded in the center to form a tenon-and-mortise steel-concrete transition segment. S8: Transport the mortise and tenon steel-concrete transition segment to the shipping terminal, use a large gantry crane to flip the hollow mortise and tenon steel-concrete transition segment that has been fabricated by inversion 180°, and hoist it into the upright position for loading onto the ship.

[0011] Based on the above technical solution, the embodiments of this application can be further improved as follows: Furthermore, after machining and milling the edges in step S5, it is necessary to ensure that the overall flatness deviation of the top surface of the pressure plate is ≤2mm. The beneficial effect of this step is that it facilitates stable assembly in the future.

[0012] Furthermore, in step S6, the butt weld of the skirt panel and the lower wall panel adopts a composite welding process of CO2 gas shielded welding for the root pass and submerged arc welding for the filler pass. The gas shielded welding material is solid welding wire G55A4UC1ZSN2, and the submerged arc welding material is S49A4UFB-SUG35H5 welding wire-flux combination.

[0013] Furthermore, in step S7, when symmetrically welding the circumferential butt welds between the lower wall plate and lower corner plate of the two units and the upper wall plate and upper corner plate, a single-sided welding double-sided forming CO2 gas shielded welding process is selected. The bevel is opened on the side of the lower wall plate and lower corner plate and faces the outside of the tower. The solid welding wire G55A4UC1ZSN2 is used for the root pass gas shielded welding, and the flux-cored welding wire T554T1-1C1A-N3UH5 is used for the fill and cover pass gas shielded welding.

[0014] Furthermore, the specific welding sequence of the wall panel welding studs in step S4, the wall panel welding studs in step S6, and the skirt welding studs in step S6 is as follows: gradually expand outwards from the center of the workpiece along its length direction to reduce welding deformation.

[0015] This application also discloses a method for installing a tenon-and-mortise type steel-concrete transition segment for a cable-stayed bridge tower, including the following steps: The mortise and tenon steel-concrete transition segment is hoisted onto the concrete tower column. Dense steel bars are tied inside the mortise and tenon steel-concrete transition segment. After the concrete is poured, the outer surface of the skirt panel of the mortise and tenon steel-concrete transition segment is flush with the outer surface of the concrete tower column, thus realizing the mortise and tenon structure connection.

[0016] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages: 1. This application innovatively proposes a mortise and tenon type steel-concrete transition force transmission structure, which greatly enhances the connection performance between the steel structure and the concrete structure of the pylon and improves the safe service durability of the steel bridge.

[0017] 2. This application adds a stable support system for the hollow steel-concrete transition segment, which not only increases the overall rigidity of the mortise and tenon type steel-concrete transition segment to reduce deformation during in-plant welding and hoisting, but also allows the segment to be properly positioned for loading and shipping after being turned over, and to be poured into the concrete as a stiffening frame, reducing deformation during on-site hoisting and concrete construction.

[0018] 3. This application discloses a method for manufacturing mortise and tenon type steel-concrete transition segments, and determines the overall assembly scheme for manufacturing mortise and tenon type steel-concrete transition segments for cable-stayed bridge towers, effectively ensuring the assembly gap requirements of each plate and improving the overall manufacturing accuracy of the steel-concrete transition segments.

[0019] 4. This application adopts the inverted method to manufacture steel-concrete transition segments, which facilitates the transfer of steel-concrete transition segments within the factory, significantly reduces the lifting capacity requirements of the workshop, and effectively controls the planar accuracy of the upper end face of the steel-concrete transition segments. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the mortise and tenon steel-concrete transition segment of the cable-stayed bridge tower according to a specific embodiment of the present invention; Figure 2 for Figure 1 A schematic diagram of the structure after the removal of the stabilizing support system; Figure 3 for Figure 1 Schematic diagram of the rear structure of the mid-skirt panel unit and the lower panel; Figure 4 for Figure 1 Schematic diagram of the structure of the pressure-bearing plate body; Figure 5 for Figure 1 A schematic diagram of the structural support system in the middle; Figure 6 This is a flow chart illustrating the manufacturing method of the mortise and tenon steel-concrete transition segment of the cable-stayed bridge tower according to a specific embodiment of the present invention. Figure 7 This is a schematic diagram of the installation of the tenon-and-mortise steel-concrete transition segment of the cable-stayed bridge tower according to a specific embodiment of the present invention; The specific reference numerals in the attached figures are as follows: 1-Exterior wall panel unit; 2-Skirt wall panel unit; 3-Stable support system; 4-Pressure-bearing plate body; 5-Cable guide anchor hole; 6-Two-piece unit; 7-Tenon and tenon steel-concrete transition segment of cable-stayed bridge tower; 101 - Upper wall panel; 102 - Upper corner panel; 103 - Lower wall panel; 104 - Lower corner panel; 105 - Wall panel welding stud; 201 - Skirt panel; 202 - Vertical stiffening rib; 203 - Horizontal stiffening rib; 204 - Skirt welding stud; 401 - Hollowed-out pressure plate; 402 - Anchor web; 403 - Pressure plate stiffening rib. Detailed Implementation

[0022] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the technical solution of the present invention and are therefore intended to limit the scope of protection of the present invention.

[0023] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0024] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0025] To better understand the above technical solutions, the following will provide a detailed description of the technical solutions in conjunction with the accompanying drawings and specific embodiments.

[0026] Example 1: like Figure 1-5 As shown in the embodiment, this application discloses a mortise and tenon type steel-concrete transition segment for cable-stayed bridge towers. Specifically, it is applied to the junction of the middle and upper tower columns of the cable-stayed bridge tower in the main channel bridge. The design in this application is a pressure-bearing shear-transfer structure containing a 120mm ultra-thick pressure plate. The pressure plate is designed as a hollow structure embedded in the concrete middle tower column, and pressure plate stiffening ribs are set on its upper part to increase the local pressure-bearing area, effectively solving the problem of the connection between the large cross-section pressure plate and the concrete tower column in the fully pressure-bearing steel-concrete transition segment. Preferably, the insertion height into the concrete in this application is 5.5m, and it is connected to the concrete by welding studs. The fully enclosed steel tower outer wall panel structure is 2.5m high, and multiple trapezoidal skirt wall panels are set at the bottom to form a mortise and tenon structure.

[0027] The specific structure of this application includes: External wall panel unit 1; Multiple skirt panel units 2 are installed at intervals on the bottom side of the outer wall panel unit 1; A robust support system 3 is installed inside the outer wall panel unit 1; The pressure-bearing plate 4 is installed inside the outer wall panel unit 1, and the pressure-bearing plate 4 is located above the stable support system 3. The skirt wall panel units 2 arranged at intervals in this application facilitate the installation of mortise and tenon structures during subsequent use, thereby improving the overall service life.

[0028] The pressure-bearing plate 4 includes: A perforated bearing plate 401 is installed inside the outer wall panel unit 1. The perforated bearing plate 401 is used to facilitate the installation of reinforcing bars and to pour concrete to ensure the strength of the overall structure. The perforated bearing plate 401 and the outer wall panel unit 1 are connected by welding. The thickness of the perforated bearing plate 401 is 120mm. Anchor web 402 is installed on the top of the hollowed-out pressure plate 401. The anchor web 402 is used to strengthen the strength of the entire pressure plate 4. Multiple pressure plate stiffening ribs 403 are installed at intervals on the hollow pressure plate 401. These pressure plate stiffening ribs 403 are subsequently used to insert reinforcing bars to improve strength. The pressure plate stiffening ribs 403 are divided into plate-type stiffening ribs and T-type stiffening ribs.

[0029] In one embodiment, such as Figure 3 As shown, the skirt panel unit 2 includes: Skirt panel 201; Vertical stiffening ribs 202 are installed on the back of the skirt panel 201; A horizontal stiffening rib 203 is installed on the back of the skirt panel 201, and the horizontal stiffening rib 203 is perpendicular to the vertical stiffening rib 202. That is, the vertical stiffening rib 202 and the horizontal stiffening rib 203 cooperate with each other to improve the overall strength of the skirt panel 201. Multiple skirt welding studs 204 are installed on the back of the skirt panel 201 to ensure stability during subsequent concrete pouring.

[0030] In one embodiment, the included angle between the skirt panel 201 and the outer wall panel unit 1 is α, where α = 175 ± 3°, thereby increasing the stability of the connection between the steel-concrete structural sections.

[0031] Specifically, both the outer wall panel unit 1 and the skirt wall panel unit 2 are provided with cable guide anchor holes 5.

[0032] Specifically, such as Figure 2 As shown, the outer wall panel unit 1 includes: Multiple upper wall panels 101 are spaced apart around the hollow pressure plate 401. Specifically, the distance between the bottom side of the upper wall panel 101 and the bottom side of the hollow pressure plate 401 is at least 300mm. Multiple upper corner plates 102 are provided, each upper corner plate 102 is disposed between any two adjacent upper wall plates 101, and the upper corner plate 102 is used to connect the upper wall plates 101 so that the upper wall plates 101 can surround the hollow pressure plate 401 to form a pressure plate body, which is convenient for subsequent assembly. Multiple lower wall panels 103 are spaced apart around the stable support system 3. During subsequent assembly, the lower wall panels 103 are connected to the skirt panel 201 to form a unit, and then assembled. At the same time, the stability of the unit is ensured by the stable support system 3. Multiple lower corner plates 104 are provided, each of which is disposed between any two adjacent lower wall plates 103. Similarly, the lower corner plate 104 is used to connect the lower wall plates 103 so that it is disposed around the bottom of the pressure-bearing plate body. Multiple wall panel welding studs 105 are respectively installed on the back of the upper wall panel 101, lower wall panel 103, upper corner panel 102 and lower corner panel 104, and are connected to the subsequent concrete by welding studs to ensure stability.

[0033] To ensure the strength of the overall structure and the stability of subsequent assembly, this application designs the thickness of the upper wall plate 101 and the lower wall plate 103, wherein the thickness of the upper wall plate 101 is greater than the thickness of the lower wall plate 103, so as to ensure the strength of the overall connection.

[0034] Among them, such as Figure 5 As shown, the stable support system 3 is composed of multiple horizontal, vertical and diagonal braces connected in an alternating manner.

[0035] Example 2: like Figure 6 As shown, based on Embodiment 1, this application discloses a method for manufacturing the mortise and tenon type steel-concrete transition segment of the cable-stayed bridge tower in Embodiment 1, including the following steps: S1: Fabricate the upper wall panel, lower wall panel, upper corner panel, lower corner panel, anchor web, bearing plate, skirt panel, and stable support system; the specific contents of this step are as follows: based on the relevant data such as the concrete tower column on site, design the specific dimensions of the upper wall panel, lower wall panel, upper corner panel, lower corner panel, anchor web, bearing plate, skirt panel, and stable support system, and process them separately; S2: Place multiple pressure plates on the assembly jig and assemble them. After assembly, a hollow pressure plate is formed. Then, the flatness is checked and adjusted to ensure the flatness of the hollow pressure plate. The specific content of this step is as follows: Place multiple pressure plates on the assembly jig and assemble them. After assembly, a hollow pressure plate is formed. Then, it is repaired and inspected. After passing the inspection, the assembly positions of the anchor web plate and the upper wall plate are marked on the hollow pressure plate. The flatness of the hollow pressure plate is checked with a level and a straightedge. For local areas with excessive tolerance, a combination of welding and grinding is used to ensure its overall flatness. S3: Assemble the upper wall panel and upper corner panel symmetrically around the hollowed-out pressure plate. Specifically, assemble the upper wall panel according to the assembly position defined in step S2. After assembly, check and adjust the angle. After precise adjustment, secure it and use channel steel for support and protection. First, symmetrically weld the vertical penetration fillet welds between the upper wall plate and the upper corner plate. When welding the vertical penetration fillet welds, use single-sided welding with double-sided forming CO2 gas shielded welding, with the bevel facing outwards. The gas shielded welding material is T554T1-1C1A-N3UH5 flux-cored wire (φ1.2mm). Finally, symmetrically weld the circumferential bevel fillet welds between the hollow bearing plate and the upper wall plate and upper corner plate. S4: Install the anchor web plate onto the hollow bearing plate. Specifically, use the center line of the hollow bearing plate as a reference to draw an auxiliary line, and then install the anchor web plate. At the same time, ensure the verticality of the anchor web plate, adjust it into place, and then secure it with channel steel for support and protection. First, complete the vertical full-penetration fillet weld between the anchor web and the upper wall plate. Then, symmetrically weld the horizontal full-penetration fillet weld between the anchor web and the hollow bearing plate. Finally, symmetrically weld the full-penetration fillet weld between the bearing plate stiffening rib and the bearing plate to form the bearing plate body. In addition, weld the wall plate studs on the inner walls of the upper wall plate and the upper corner plate using the electric arc stud welding method. S5: Machine mill the top edge of the pressure-bearing plate to ensure its flatness. The specific steps are as follows: Using the upper surface of the hollowed-out pressure plate as a reference surface, use an API measuring instrument to mark the machining lines on the top edge of the upper wall plate, upper corner plate, and anchor web plate. Use a portable machining tool to machine and mill the top edge of each plate unit along these machining lines. Before machining the top edge of the upper wall plate, upper corner plate, and anchor web plate, check the distance from the machining line to the pressure plate reference surface; the marking deviation must be ≤1mm. After machining, ensure the overall flatness deviation of the machined surface is ≤2mm. S6: Install the lower wall panel onto the assembly jig, then assemble the skirt panel along the longitudinal direction of the lower wall panel, and weld the butt weld. After the butt weld is completed, turn the lower wall panel over so that the inner side faces upward, and use the arc stud welding method to weld the wall panel welding studs to the lower wall panel. At the same time, use the arc stud welding method to weld the skirt panel welding studs to form two units. Use the arc stud welding method to weld the wall panel welding studs to the lower corner plate. In this step, at least two sets of assembly jigs are used, with the support plates on the two sets having a line shape of 175° and 185°, respectively, to accommodate the welding operations in the positive and negative positions of the double-sided symmetrical welding process of the skirt panel unit and the lower outer wall panel unit. At the same time, the butt weld adopts an asymmetrical X-shaped groove. Before welding, the two sides of the butt weld are heated to the preheating temperature requirement by a flexible electromagnetic induction heating belt and a reverse deformation amount is set. A composite welding process of CO2 gas shielded welding for the root pass and submerged arc welding for the filler and cover pass is selected. The gas shielded welding material is solid welding wire G55A4UC1ZSN2 (φ1.2mm), and the submerged arc welding material is S49A4UFB-SUG35H5 (φ5.0mm). During the welding process of the welding wire-flux combination, the joint is turned over multiple times to alternate welding according to the deformation of the joint, so as to ensure the flatness of the two units of "lower wall panel + skirt panel" after welding. S7: Turn the pressure plate over 180° and place it on the jig, that is, after ensuring that the machined end face of the pressure plate is horizontal in step S5, rigidly fix the pressure plate to the jig. First, the stable support system is set up on the jig, and the two-piece unit is assembled to the upper wall of the pressure plate. After completion, the two-piece unit is constrained with the steel support frame of the stable support system to prevent the plate unit from overturning. The stable support system consists of horizontal braces, vertical braces, and diagonal braces, and is set below the pressure plate. The constraint adopts a welded connection to increase the overall rigidity of the mortise and tenon steel-concrete transition segment, so as to reduce the deformation of the segment during the welding and hoisting process. Because the skirt panel has insufficient rigidity, outriggers need to be set in the stable support system. The stable support system is used to realize the correct position of the segment after it is overturned and shipped. In addition, during the subsequent on-site erection, the stable support system can reduce the deformation of the segment during on-site hoisting and concrete construction. Finally, it can be poured into the concrete as a stiffening skeleton. Then, assemble the lower corner plates between adjacent units. Specifically, assemble the lower corner plates using the horizontal baseline of the two units as a reference, aligning the horizontal baselines of adjacent units. Check the tilt angle and opening size of the lower wall plates to ensure that the deviation of the upper and lower opening sizes is ≤2mm. After meeting the requirements, position and secure each lower wall plate and lower corner plate, and rigidly connect and fix them to the stable support system. Symmetrically weld the vertical penetration fillet welds between the lower wall plates and lower corner plates of the two units. Symmetrically weld the lower wall plates, lower corner plates, and upper wall plates of the two units in a centered manner. The circumferential butt welds between the plates form a tenon-and-mortise type steel-concrete transition segment; when welding the circumferential butt welds between the lower wall plate and lower corner plate of the two-piece unit and the upper wall plate and upper corner plate, a single-sided welding double-sided forming CO2 gas shielded welding process is adopted. The bevel is opened on the side of the lower wall plate and lower corner plate and faces the outside of the tower. The solid welding wire G55A4UC1ZSN2 (φ1.2mm) is used for the root pass gas shielded welding, and the flux-cored welding wire T554T1-1C1A-N3UH5 (φ1.2mm) is used for the fill and cover pass gas shielded welding.

[0036] S8: Transport the mortise and tenon steel-concrete transition segment to the shipping terminal, use a large gantry crane to flip the hollow mortise and tenon steel-concrete transition segment that has been fabricated by inversion 180°, and hoist it into the upright position for loading onto the ship.

[0037] The specific welding sequence of the wall panel welding studs in step S4, the wall panel welding studs in step S6, and the skirt welding studs in step S6 is as follows: gradually expand outwards from the center of the workpiece along its length to reduce welding deformation; it is important to leave 2 to 3 rows of cylindrical head welding studs near the corner welds of the block and the butt joints of the box opening unwelded, and then weld them after the corner welds of the block or the butt joints of the box opening are completed.

[0038] Example 3: like Figure 6 As shown, based on Embodiment 1, this application discloses the installation of the mortise and tenon type steel-concrete transition segment of the cable-stayed bridge tower in Embodiment 1, including the following steps: The mortise and tenon steel-concrete transition segment of the cable-stayed bridge tower is hoisted onto the concrete tower column. Dense steel bars are tied inside the mortise and tenon steel-concrete transition segment of the cable-stayed bridge tower. After the concrete is poured, the outer surface of the skirt panel of the mortise and tenon steel-concrete transition segment of the cable-stayed bridge tower is flush with the outer surface of the concrete tower column, realizing the mortise and tenon structure connection.

[0039] Numerous specific details are set forth in this specification. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0040] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A mortise-and-tenon type steel-concrete transition segment for cable-stayed bridge towers, characterized in that, include: External wall panel unit; Multiple skirt panel units are installed at intervals on the bottom side of the outer wall panel unit; A robust support system is installed inside the outer wall panel unit; The pressure-bearing plate is installed inside the outer wall panel unit, and the pressure-bearing plate is located above the stable support system; The pressure-bearing plate body includes: A perforated pressure-bearing plate is installed inside the outer wall panel unit; An anchor web plate is installed on top of the perforated bearing plate; Multiple pressure-bearing plate stiffening ribs are installed at intervals on the hollow pressure-bearing plate.

2. The mortise and tenon type steel-concrete transition segment for cable-stayed bridge towers according to claim 1, characterized in that, The skirt panel unit includes: Skirt panel; Vertical stiffening ribs are installed on the back of the skirt panel; A transverse stiffening rib is installed on the back of the skirt panel, and the transverse stiffening rib is perpendicular to the vertical stiffening rib; Multiple skirt-shaped welding studs are installed on the back of the skirt panel.

3. The mortise and tenon type steel-concrete transition segment for cable-stayed bridge towers according to claim 2, characterized in that, The included angle between the skirt panel and the outer wall panel unit is α, where α = 175 ± 3°; Both the outer wall panel unit and the skirt wall panel unit are provided with cable guide anchor holes.

4. The mortise and tenon type steel-concrete transition segment for cable-stayed bridge towers according to claim 3, characterized in that, The outer wall panel unit includes: Multiple upper wall panels are spaced apart around the perforated pressure plate; Multiple upper corner plates, each of the upper corner plates being disposed between any two adjacent upper wall plates; Multiple lower wall panels are spaced apart around the stable support system; Multiple lower corner plates, each of the lower corner plates being disposed between any two adjacent lower wall plates; Multiple wall panel welding studs are respectively installed on the back of the upper wall panel, lower wall panel, upper corner panel and lower corner panel; The stable support system is composed of multiple horizontal, vertical, and diagonal braces connected in an interlaced manner.

5. A method for fabricating a mortise-and-tenon type steel-concrete transition segment for a cable-stayed bridge tower, characterized in that... Includes the following steps: S1: Fabrication of upper wall panel, lower wall panel, upper corner panel, lower corner panel, anchor web, bearing plate, skirt panel and stabilizing support system; S2: Place multiple pressure plates on the assembly jig and assemble them. After assembly, a hollow pressure plate is formed. Then, the flatness is checked and adjusted to ensure the flatness of the hollow pressure plate. S3: Assemble the upper wall panel and upper corner panel symmetrically around the hollowed-out pressure plate. After assembly, perform angle detection and adjustment. After precise adjustment, secure the plate and use channel steel for support and protection. First, symmetrically weld the vertical penetration fillet weld between the upper wall plate and the upper corner plate. When welding the vertical penetration fillet weld, use single-sided welding with double-sided forming CO2 gas shielded welding, with the bevel facing outward. The gas shielded welding material is flux-cored wire T554T1-1C1A-N3UH5. Finally, symmetrically weld the circumferential bevel fillet weld between the hollow bearing plate and the upper wall plate and the upper corner plate. S4: Install the anchor web plate onto the hollow bearing plate, while ensuring the verticality of the anchor web plate. After adjusting it into place, secure it and use channel steel for support and protection. First, complete the vertical full-penetration fillet weld between the anchor web and the upper wall plate. Then, symmetrically weld the horizontal full-penetration fillet weld between the anchor web and the hollow bearing plate. Finally, symmetrically weld the full-penetration fillet weld between the bearing plate stiffening rib and the bearing plate to form the bearing plate body. In addition, weld the wall plate studs on the inner walls of the upper wall plate and the upper corner plate using the electric arc stud welding method. S5: The top edge of the pressure plate is machined and milled to ensure the flatness of the top edge; S6: Install the lower wall panel onto the assembly jig, then assemble the skirt panel along the longitudinal direction of the lower wall panel, and weld the butt weld. After the butt weld is completed, turn the lower wall panel over so that the inner side faces upward, and use the arc stud welding method to weld the wall panel welding studs to the lower wall panel. At the same time, use the arc stud welding method to weld the skirt panel welding studs to form two units. Use the arc stud welding method to weld the wall panel welding studs to the lower corner plate. S7: Turn the pressure-bearing plate over 180° and place it upside down on the jig; First, the stable support system is set on the jig, and the two-piece unit is assembled to the upper wall of the pressure-bearing plate. After completion, the two-piece unit is constrained to the steel support frame of the stable support system to prevent the plate unit from overturning. Then, the lower corner plate is assembled between the two adjacent units; the vertical penetration fillet welds between the lower wall plates and the lower corner plates of the two units are symmetrically welded, and the circumferential butt welds between the lower wall plates and lower corner plates of the two units and the upper wall plates and upper corner plates are symmetrically welded in the center to form a tenon-and-mortise steel-concrete transition segment. S8: Transport the mortise and tenon steel-concrete transition segment to the shipping terminal, use a large gantry crane to flip the hollow mortise and tenon steel-concrete transition segment that has been fabricated by inversion 180°, and hoist it into the upright position for loading onto the ship.

6. The manufacturing method according to claim 5, characterized in that, After the edge milling in step S5, it is necessary to ensure that the overall flatness deviation of the top surface of the pressure plate is ≤2mm.

7. The manufacturing method according to claim 5, characterized in that, In step S6, the butt weld between the skirt panel and the lower wall panel is performed using a composite welding process of CO2 gas shielded welding for the root pass and submerged arc welding for the filler pass. The gas shielded welding material is solid welding wire G55A4UC1ZSN2, and the submerged arc welding material is S49A4UFB-SUG35H5 welding wire-flux combination.

8. The manufacturing method according to claim 5, characterized in that, In step S7, when symmetrically welding the circumferential butt welds between the lower wall plate and lower corner plate of the two units and the upper wall plate and upper corner plate, a single-sided welding double-sided forming CO2 gas shielded welding process is selected. The bevel is opened on the side of the lower wall plate and lower corner plate and faces the outside of the tower. The solid welding wire G55A4UC1ZSN2 is used for the root pass gas shielded welding, and the flux-cored welding wire T554T1-1C1A-N3UH5 is used for the fill and cover pass gas shielded welding.

9. The manufacturing method according to claim 5, characterized in that, The specific welding sequence for the wall panel welding studs in step S4, the wall panel welding studs in step S6, and the skirt welding studs in step S6 is as follows: gradually expand outwards from the center of the workpiece along its length to reduce welding deformation.

10. A method for installing mortise-and-tenon type steel-concrete transition segments of cable-stayed bridge towers, characterized in that... Includes the following steps: The mortise and tenon steel-concrete transition segment of the cable-stayed bridge tower as described in any one of claims 1-4 is hoisted onto the concrete tower column. Dense steel bars are tied inside the mortise and tenon steel-concrete transition segment of the cable-stayed bridge tower. After the concrete is poured, the outer surface of the skirt panel of the mortise and tenon steel-concrete transition segment of the cable-stayed bridge tower is flush with the outer surface of the concrete tower column, thereby realizing the mortise and tenon structure connection.

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